The present invention relates generally to stump grinding machines of the type having a grinding wheel located at the end of a movable arm structure. More particularly, the invention relates to a stump grinding machine incorporating a novel turntable arrangement for mounting of the engine.
Stump grinding machines are widely used to remove tree stumps. The stump is removed by a driven grinding wheel located at the end of the machine's movable cutting arm. Typically, the grinding wheel is swept back and forth across the tree stump. With each sweep, the grinding wheel is lowered slightly until the entire stump has been removed. The final sweeps of the grinding wheel may be below ground level to ensure that the entire stump has been eliminated.
Often, stump grinding machines are constructed on a wheeled frame to facilitate movement of the machine from place to place. The frame may be self-propelled, or configured to be towed behind another vehicle. Power to drive the grinding wheel is derived from an engine, typically a gasoline or diesel engine, located on the wheeled frame. A series of belts are generally provided to transfer engine power to the grinding wheel. Often, the engine has been mounted on the arm structure, which is in turn connected to the frame for pivotal movement in both horizontal and vertical planes.
While these arrangements have worked generally well, they are not without disadvantages. For example, the engine adds weight to the arm structure. In addition, placement of the engine in this location tends to raise the center of gravity of the overall machine. It has often been necessary to compensate for the higher center of gravity by providing a wider frame structure. A wider frame structure, however, is often not desirable since it can limit the ability of the stump grinding machine to pass through narrow gates and the like. This arrangement can also limit the angular extent of the sweep and the vertical arc through which the grinding wheel can move.